Coal burning generating electric loco-motive with improved ash separation and storagesystem



Oct. 28, 1958 J. I. YELLOTT ETAL 2,857,854

COAL BURNING GENERATING ELECTRIC LOCOMOTIVE WITH IMPROVED ASH SEPARATION AND STORAGE SYSTEM Filed Jan.

ATT RNEY-s' United States PatentO COAL BURNING GENERATING ELECTRIC LOCO- MOTIVE WITH IMPROVED ASH SEPARATION AND STORAGE SYSTEM John I. Yellott, New York, N. Y., and Peter R. Broadley,

Elizabeth, N. J., assignors to Bituminous Coal Research, Inc., Washington, D. C., a corporation of Delaware Application January 7, 1953, Serial No. 330,076

11 Claims. (Cl. 105-35) This invention relates to systems for separating ash, slag, and incompletely burned combustibles from the products of combustion resulting from the pressurized combustion of pulverulent solid combustibles, and residue-forming fluent combustibles generally, and to means for quenching and storing theseparated solids. More particularly, the invention is concerned with the separation and storage of ash and other residues of combustion in a self-powered, coal-burning locomotive, desirably of the generating electric type, in which the generators are driven by a prime mover actuated by cleaned combustion gases, suitably tempered with-cooling air.

In our prior application, Ser. No. 257,702, filed November 23, 1951, for Vortical Whirl Separators and Method of Operation, there has been shown novel ,sepa-,

rating equipment specially adapted for the removal of suspended solids from gasiform fluids, of the type of pressurized combustion gases from the combustion of pulverulent solid combustibles as streaming entrainments of such solids in a pressurized combustive air stream. In our companion application Ser. No. 330,077, filed January 7, 1953, for Coal-Burning Gas Turbine Power Plants Incorporating Novel Self-Supporting and Pressure Sustaining Vortical Whirl Separators Together With Improved Ash Quenching and Blowdown Means, there is shown an improved ash separating system particularly adapted for high temperature, high pressure installations, such as coal burning, gas turbine-powered generating electric power plants for use in locomotives.

The removal of any and all forms of entrained solids from stack gases of factories, locomotives, and other installations has now become imperative, as a result of legislative action on air pollution and smoke control, and, also, as a result of increased appreciation of the fact that considerable economic Waste results, as well as a continuing menace to public health. With the advent of systems for the pressurized combustion of pulverized blowdown stream, followed by the quenching and stor+ age, of the separated residues, and the venting, of the cleaned gas from this final ash concentrating step to the atmosphere, or to the coal drying and pulverizing sys'- tem, where used.

The desirable results of the present invention are secured, in one embodiment of the invention, as incorporated in a locomotive assembly, wherein, a storage; tank, containing a body of water, serves to receive the 1 concentrated ash blowdown stream from the ash concentrator, the solids-bearing air stream discharging through a special diffusing nozzle into the water, and

substantially at atmospheric pressure.

It is, therefore, among thefeatures of novelty and advantage of the present invention to provide an improved ash disposal and storage system for pressurized combustion systems using powdered coal or other residue-forming fuels.

A main feature of novelty and advantage of the inven tion herein is the provision of gas turbine-powered, pow-- dered coal-burning locomotives with a self-contained ash;

separation, quenching and storage system.

Another feature of novelty and advantage of the invention herein is the provision of powdered coal-burning locomotives with special ash separation and storage mean in which the separated ash and other combustion residues are pneumatically handled in a side stream of motive fluid and delivered to wet storage.

It is also a feature of novelty and advantage of the invention herein to provide an improved ash separation,

disposal and storage system, characterized by the fact that the detritusis gas-borne, and

mechanical handling means are eliminated. i

A further feature of novelty and advantage of the present invention is the provision of ash storage means corn-- prising a water-containing tank wherein discharged ash is converted into and stored as a readily disposable slurry.

Another feature of novelty and advantage of the invention is the provision of means for diffusing a concentrated ash blowdown stream, at substantially atmospheric pressure, into a body of water, whereby a slurry is formed, and the water is not blown out by the entrain-- ing gas. r w An additional feature of novelty andadvantage of the invention herein is the provision of a specially designed diffuser for introducing gas-borne pulveriforrn solids intoa body of quenching fluid to form a slurry, the difiuser coal and other residue-forming fuels, the problems of ash separation are compounded by the necessity of concomitantly quenching and removing incompletely burned fuel particles, as well asremoving and storing fine ash particles. In locomotive installations, it is undesirable to vent or discharge combustion residue incorporating any significant amounts of fine ash particles, while the locomotive is in transit. All combustion residues from the .pressurized combustion of powdered coal, or like fuel,

incorporating flow restrictor means, whereby the pressure of the solids-bearing gas stream is reduced to substantially that of the ambient atmosphere.

Wtih these and other desirable features of novelty and advantage, which may be incident to the improvements herein, the invention consists in the parts and combinations to be hereinafter set forth and claimed, with the understanding thatthe several necessary elements comprising the invention, may be varied in construction,

proportions and arrangements, without departing from the spirit and scope of the appended claims.

In order to make the invention more clearly understood, there is shown in the accompanying drawings means for carrying the same into practical effect, without limiting the improvements in theiruseful application to the particular constructions, which, forthepurpose of explanation, have been made the subject of illustration.

In the drawings, like numerals refer to similarparts throughout the severalviews, of which a Figure 1 is a schematic showing of a generating electric locomotive incorporating a powdered coal-burning gas turbine power plant for actuating the generators, and an ash separating system including an ash concentrator and blowdown line to an ash quenching and storage tank;

Fig. 2 is a schematic showing of an ash concentrator;

Patented Oct. 28, 1958 with blowdown line to the ash disposal unit, and cleaned gas efferent lines;

Fig. 3 is a fragmentary side elevation of a fish-tail diffuser nozzle of the ash disposal 'unit of Fig. 2, and

Fig. 4 is a fragmentary elevation of a pressure air system for supplying cooled, coal-carrying combustive air, and cooled blowdown air to the power plant of Fig. 1.

Turning now to the drawings, the locomotive comprises a cab mounted on a chassis 11, which is operatively supported on trucks 12, 13, and electrically driven by motors powdered by generators 14, which are mechanically powered by gas turbine 15. The stack 16 mounts a regenerator which is supplied with compressed air from a discharge duct of the main air compressor 18, driven by turbine 15. The regeneratively heated air discharges through one or more expansion ducts 19 into alike number of combustors, designated generally by the numeral 20. Usually, two combustors are used. A pulverized coal storage tank 21 and subjoined coal pump 22 are mounted adjacent the combustors, and coal is delivered from the pump into combustive air line 23, and thence through splitter 24 and combustor feed lines 25, to the combustors 20. The high pressure conveying air is supplied to the coal pump in the following manner: A line 26 is tapped into the secondary air duct 17 (Fig.4), and supplies air through an intercooler 26A to the constant displacement booster compressor 27, having a discharge line 28. The lines 28 and 23 are rectilinearly aligned in the pump 22, and respectively serve as conveying air inlet and outlet lines, as more particularly set forth and claimed in pump applications already on file, namely, John I. Yellott, Serial No. 361,802, filed June 15, 1953, for Improved Rotary Solids Transfer Pump for Handling Fluidized Solids, now Patent No. 2,750,234, issued June 12, 1956, and John I. Yellott, Serial No. 363,524, filed June 23, 1953, for Rotary Solids Transfer Pump, now Patent No. 2,750,233, issued June 12, 1956. A motor'29, powered by an auxiliary D. C. motor of the generator assembly 14, serves to drive the booster compressor 27, and its speed may be controlled by any suitable control device, designated generally by the numeral 29'. A separately controlled branch line 28 serves to supply cooling blowdown air to the ash'blowdown manifold of the ash separating system, to be described more in detail hereinafter.

"The combustors 20 discharge ash and combustion residue-bearing combustion gases to the subjacent ash separator 30 through elbow ducts 33, and the cleaned gasfrom the separator is delivered to the turbine through expansion duct or ducts 35. The combustors are more particularly described and claimed in the application of Frederick D. Buckley, Serial No. 257,165, filed November 19, 1951, for Cold Wall Combustor With Flexibly Mounted Flame Tube, now Patent No. 2,823,627, dated February 18, 1958, and the novel separator assembly is more particularly described and claimed in our companion application Ser. No. 330,077, hereinabove identified. The combustors are desirably of the improved type disclosed in the Buckley application, and include novel duplex coal and oil burners of the type disclosed and claimed in the application of Paul M. Rotzler, Ser. No. 257,079, filed November 19, 1951,'for Powdered Coal Burner For Pressurized Combustors.

The ash separator assembly 30 is comprised of a main, generally cylindrical'conduit, divided longitudinally by a sloping separator plate 31 into a lower, dirty gas plenum chamber 32, in fluid communication with the superjacent combustor through elbow' duct 33, and an upper, cleaned gas plenum chamber 34, in fluid communication with turbine through expansion duct 35. A battery of vertical whirl separators, designated generally by the numeral 36, is subjoined to and severally in fluid communication with the dirty gas plenum chamber, and their cleaned gas outlet tubes, not shown, connect the-individual separators 37 with the cleaned gas plenum chamber 34. The ash blowdown lines of the separators are severally designated by the numeral 38, and jointly discharge into ash discharge manifold 39, which, as shown, discharges tangentially into the upper portion of ash concentrator 40. The manifold 39 may be supplied with coolant air through line 28' (Fig. 4), as described hereinabove.

The ash concentrator 40 is a vertical whirl separator of the same type as the self-supporting, pressure-sustaining vortical whirl separators 37, whose detailed construction and function is described andclaimed in our said aboveidentified companion application Ser. No. 330,077. The ash concentrator is of appreciably smaller capacity than any of the main battery separators, and is designed to handle the combined ash-carrying blowdown streams from such separators. Thus, if there are ten (10) separators in a battery, and each one has a throughput capacity of 1500 C. F. M., with a blowdown stream of from .5 up to 1.5 percent, that is, from 7.5 to 22.5 C. F. M. per tube or separator, the total input of the ash concentrator will be 75 to 225 C. F. M. of motive fluid, which fluid will carry all of the separated ash of the system. When this concentrated ash-carrying fluid is processed in the ash concentrator, it will be seen that the cleaned gas will be comprised of from about 67.5 to 202.5 C. F. .M. of the original dirty motive fluid, and the ash blowdown stream from the ash concentrator will vary from 7.5 to 22.5 C. F. M., which means that the total amount of original motive fluid required to remove the separated ash from the combustion system will vary between 0.05% and 0.15%, which is a highly efficient procedure, and noteworthy because of the fact that no extraneous mechanical equipment or power is made use of for ash removal.

As shown in Fig. 2, the ash concentrator 40 includes the usual barrel section 41 having a vortical whirlimparting inlet means 39, previously described, an axial cleaned gas outlet 42 having its mouth depending below the inlet into the primary separator chamber formed by the barrel 41, and a bottom discharge chamber 43, in fluid communication with the barrel section through an axially apertured razor plate having upstruck peripheral skimmer blades defining peripheral apertures, the plate being designated generally by the numeral 44. A tangential ash blowdown line 45 connects the bottom of the discharge chamber wall with the ash disposal unit, designated generally by the numeral 50. As shown in Fig. 1, the cleaned gas outlet 41 of the ash concentrator 40 discharges into the turbine exhaust stack through angular extension 41a. The ash disposal blowdown line 45 discharges into a T connection 46 (Fig. 2), having a valved side arm 47, for blowofi purposes, a top clean-out plug 48, and a depending leg 49 connected through convergent ash nozzle 51 to the upper, tubular entrant 52 of fish-tail diffuser 53. As seen in Fig. 3, the difiuser tapers towards a closed bottom 54, and the front and back walls of the diffuser are perforated, as indicated at 55. The diffuser dips well below the surface of a body of water 56 contained in a semi-closed tank 57, having a sloping bottom 58, as shown. Water is introduced into the tank through line 59, and a valved slurry outlet 58a is provided at the bottom of the tank.

The tank, as indicated above, is maintained at atmospheric pressure, by providing suitable splash guards, not shown, at the top, so that the residual cleaned gas of the ash separating system can be vented to the atmosphere. In operation, the concentrated ash blowdown stream from blowdown line 45 discharges through T 46 and convergent nozzle 51, into the diffuser 53. In passing through the nozzle, the pressure of the issuing gas stream is reduced to atmospheric. The area of the holes in the diffuser is sufiicient to reduce the velocity of the air stream to about 20 F. P. S. At this velocity, the gas stream will bubble through the apertures in the fish-tail difluser at such a relatively slow rate that it will break gently into myn'ads of fine bubbles, which will collapse at the surface of the water, and the particles of ash will be thoroughly wetted and fall to the bottom of the tank, where they will even tually build up into a fluent slurry which can be drained off through valved outlet 58a at any other suitable time.

By the improvements described immediately above, the ash is continuously removed from the turbine motive fluid, and stored, in an innocuous condition, on the, locomotive, from which it can be discharged at approved points. If the ash nozzle and/or the diffuser becomes plugged, the clean-out plug may be removed to permit access to the interior of the device. If, for any reason, the ash is not to be separated and stored, the valved bypass line may be opened, and the concentrated ash blowdown stream vented to the atmosphere, or to test equipment, if the system is under test.

As noted, in the form of the invention incorporated in the locomotive of Fig. 1, the cleaned gas from the ash concentrator is vented to the regenerator housing of the turbine exhaust stack. In this showing of a locomotive, the coal is carried on the locomotive in dry, pulverized form. When the coal is carried as bunker coal, as in the patent to John I. Yellott, No. 2,533,866, issued December 12, 1950, for Generating Electric Locomotive With Coal-Fired Gas Turbine, and the coal is pulverized on the locomotive or in a coal storage and preparation car coupled to the locomotive, it is necessary to provide a source of heat for drying the coal. This can bedone by utilizing hot exhaust gases from the turbine stack, or, as'is about to be shown, by using the still hot, cleaned gas from the ash concentrator. gas outlet 42 of the ash concentrator 40 is connected to a As shown in Fig. 2, the cleaned cruciform, 4-way connection 60. This member is provided with a valved upper branch 61 incorporating a convergent no-zzle flow restrictor 62. Valved side arms are severally connected to a blowotf line 63 and to the coal drying system 64. The valved line 61 can be vented to the atmosphere through the ,regenerator housing of the exhaust stack. If the cleaned, hot gas is to be used in the coal drying system, valved line 64 is opened, and valved lines 61 and 63 are closed. If the cleaned gas is to be vented directly to the atmosphere,valved line 63 is opened and lines 61 and 64 are closed. Line 63 may also function to return the cleaned hot gas to the turbine inlet, the valved lines 61 and 64 again being shut ofl.

The simplicity of the ash separating and disposal system herein is enhanced by the special storage system in which the ash is collected as a fluent slurry in a water bath. The capacity of the ash storage tank is such that a sufficient quantity of water is available at all times to maintain a slurry of sufiicient fluidity to permit the removal of the slurry from the tank by simple gravity drainage, when the valved slurry discharge pipe is opened. Any losses in the volume of the water in the slurry tank, due to steam formation when hot ash contacts the water bath, can be made up, en route, by transferring water, from Water storage tank 9, on the locomotive, through water feed line 59. Any suitable water level-controlling device, not shown, may be associated with the tank 57, automatically to control the input of water into the ash storage tank.

The locomotive herein may include a small diesel engine, not shown, for hostling the engine, and oil therefor may be stored in tank 8, slung under the locomotive chassis, adjacent the water storage and ash storage tanks, all as shown in Fig. 1.

There has been described and illustrated a system capable of performing all of the specifically mentioned objects of this invention, as well as others which are apparent to those skilled in the art. Various uses of the present invention may be made employing the described structures in their conjoint, cooperative assembly. Accordingly, it is apparent that variations as tooperation, size and shape, and rearrangement of the elements may tion. Therefore, limitation is sought only in accordance with the scope of the following claims.

What is claimed is: t

1. Separator and storage system for the separation of particulate matter carried as streaming entrainments of discrete particles in gasiform fluids, comprising, in combination, a source of particle-bearing gasiform fluids; a first separating means connected to said source, and comprising at least one flat bottomed, reverse flow vortical whirl separator having a tangential blowdown line for separated particles at the bottom of the separator; an ash concentrator comprising a second said separator of lesser capacity coupled to said first blowdown line; means for venting cleaned gas from said ash concentrator; a second blowdown line discharging separated particles from said ash concentrator, said second blowdown line incorporating a pressure-reducing nozzle and a distributor at the, discharge end thereof; a quenching and storage tank con-v taming water; and means for mounting the distributor in,

the tank, below the water level, whereby the gas-borne particles discharged through the distributor are dispersed in the water to form a slurry, and the liberated gas is discharged to the atmosphere.

2. Separator and storage system according to claim 1, characterized by the fact that the distributor for the gas-borne separated particles is perforated.

3. Separator and storage system according to claim 1, characterized by the fact that the distributor for the gasborne separated particles is perforated and of fish-tail shape.

4. Separator and storage system for the separation of solid particles carried as streaming entrainments of discrete particles in gasiform fluids, comprising, in combi nation, a source of solid particle-bearing gasiform fluid; a first separating means connected to said source, and comprising a plurality of flat-bottomed, reverse flow vertical whirl separators forming a battery; the said separators severally incorporating axial discharge means for cleaned gas in the barrel sections, and spin-imparting means for incoming solid particle-laden gasiform fluid disposed about said axial discharge" means; tangential blowdown lines for separated solid particles at the bases of said separators, said blowdown lines severally incorporating flow restrictors and jointly discharging into a common manifold, the said flow restrictors preventing blowback to the separators; an ash concentrator coupled to the output of said manifold; means for venting cleaned gas from said ash concentrator at ambient pressure to the atmosphere; a separate blowdown line discharging separated particles from said ash concentrator, said blowdown line incorporating a flow restrictor, and a perforated fish-tail type distributor at the outlet end thereof; a quenching and separated solids strorage tank containing water; and means for mounting the distributor in the tank, below the water level, whereby the gas-borne solids discharged through the distributor are quenched and dispersed in the water to form a slurry, and the: cleaned gas is discharged to the atmosphere.

5. Separator and storage system according to claim 4, characterized by the fact that the individual separators severally constitute pressure vessels and are heat resistant, and the solids-bearing gasiform fluid is an ashcontaining, highly heated motive fluid for gas turbines.

6. A generating electric locomotive of the character described, comprising a locomotive cab; a chassis mounting the cab; spaced trucks supporting the chassis; motordriven wheels mounted in the trucks; motor control means in the cab; generators in the cab and coupled to the driving motors through said controls; a gas turbine mounted in the cab and operatively coupled to the generators; motive fluid generating means for the turbine mounted in the cab, and comprising at least one pressurized combustor, a pulverulent fuel supply for the c'ombustor, and c-ombustive air feed means coupling the fuel supply and the combustor; conduit means coupling the combustor and the turbine, and eflective to deliver motive fluid generated in the combustor to the turbine; a first ash separating means in said conduit means effective to separate ash from the motive fluid and deliver the cleaned motive'fiuid to the turbine; a second ash separating means; means connecting said ash separating means and efiective to deliver the ash separated in the first separator to the second separator in a blowdown stream of the motive fluid, the second separator functioning as an ash concentrator; cleaned gas discharge means in the ash concentrator in fluid connection with the turbine exhaust; ash blowdown means coupling the ash concentrator and an ash storage tank; a body of water in the tank; a flow restrictor and a diffuser at the terminal end of said second ash blowdown means, said difluser depending into said body of water, whereby a concentrated ash-bearing blowdown stream of gaseous fluid is diffused into the water at atmospheric pressure, and the entrained solids form a slurry in and with the water, while the entraining gas is vented to the atmosphere.

7. Generating electric locomotive according to claim 6 characterized by the fact that the first ash separator is comprised of a battery of flat-bottomed, reverse flow vortical whirl separators having a common discharge manifold for the ash blowdown lines, and the ash concentrator 'is a single vortical whirl separator having its intakecoupled to said discharge manifold.

8. In a powdered coal-burning locomotive of the character described wherein powdered coal is burned under pressure and the gaseous products of combustion are diluted and cooled with secondary air to form a prime mover-actuating motive fluid, the prime mover being operatively coupled to the locomotive driving mechanism, and the motive fluid is cleaned before delivery to the prime mover by passage through a battery of flat-bottomed, reverse flow vortical whirl separators wherein the. separated solid combustion residues are discharged to a common manifold coupled to said separators by blowdown lines carrying the said residues in blowdown streams comprised of fractional'amounts of the motive fluid,'the improvements comprising an ash concentrating and. storage system including a vortical whirl ash'concentr-ator coupled to said common discharge manifold, and receiving motive fluid-borne residues therefrom, said concentrator being effective to clean said entraining motive fluid and discharge the separated residues as a concentrated aerosol, and means for quenching and storing the separated solid residues comprising a tank, a body of' water in the tank, and a delivery line for the concentrated aerosol discharging into said tank, whereby the separated combustion residues form a slurry in and with the water in the tank.

9. Powdered coal-burning locomotive according to claim 8, characterized by the fact that the delivery line for the concentrated aerosol incorporates a flow restrictor; whereby the pressure of the entraining gaseous fluid is reduced to atmospheric and its velocity to less than 20 F. P. S.

10. Powered coal-burning locomotive according to claim 9, characterized by the fact that the aerosol delivery line terminates in a diffuser, and the diffuser is disposed below the level of thewater in the tank.

11. In a powdered coal-burning locomotive of the character described, in which ash, incompletely burned combustible particles, and other combustion residues and aggregates are continuously pneumatically removed from the combustion system of the locomotive, the improved ash-receiving, -quenching and storage means comprising a vented tank slung beneath the locomotive, said tank containing a body of water, and separated ash blowdown means coupling the combustion system and the tank, Whereby'hot combustion residues are quenched and stored in the tank as an aqueous slurry, and the entraining gaseous blowdown fluid is vented to the atmosphere.

References Cited in the file of this patent UNITED STATES PATENTS 1,760,617 Whitmore May 27, 1930 2,298,309 Ray -c Oct. 13, 1942 2,647,588 Miller Aug. 4, 1953 

